If you are going to do it with a Pic then it seems trivial.
Use the first LO (you may need to buffer it)
Count the freq 45-75 MHz in 2.5KHz steps
Have the Pic subtract the 45MHz offset
Tune the tuner.
I doubt very much that the tuner is going to be of such narrow bandwidth
that the possible 2.5 KILOHERTZ error is significant.
What did I miss?
Martin, HS0ZED
dw wrote:
Thanks Carl,
I already have the tuner, and the pic to control it, just investigating
a way to get frequency info to the pic direct from the Jupiter.
I've seen screen-shots of your software! Extremely impressive!
You must have been at it for a few years :)
It looks pretty mature.
On Sat, 20 Jan 2007 20:59:37 -0500, "Carl Moreschi" <n4py@arrl.net>
said:
The AT-200PC autotuner from LDG, when used in conjunction with my rig
control software, ends up following the rig without having to transmit.
You
just have to tune one time on each frequency and then the tuner remembers
the settings. My program updates the tuner with a new frequency each
time
the frequency changes on the radio.
Carl Moreschi N4PY
121 Little Bell Drive
Bell Mountain
Hays, NC 28635
----- Original Message -----
From: "dw" <bw_dw@fastmail.fm>
To: "Carl Moreschi" <n4py@arrl.net>; "Discussion of Ten-Tec Equipment"
<tentec@contesting.com>
Sent: Saturday, January 20, 2007 8:23 PM
Subject: Re: [TenTec] A question for those who know whats going on under
thehood :)
Hi Carl,
Thanks greatly for your response!!
I wonder if I could monitor the op frequency anywhere inside then?
I'm still toying with the idea of controling an external tunner with a
PIC circuit.
I used to have this with my old icom, but the Jupiter has no external
band output signal.
I had thought about polling the rs232 with the PIC and then deriving the
band from there.
But then I thought it might be easier to tap onto the op frequency
somewhere inside with the PIC and send some control signal out to one of
the unused ports.
The MFJ intelli-tuners derive settings from a combination of swr,
frequency and complex Z.
But this requires a tune xmit, as the tuner has no other way of knowing
op frequency.
I guess, If I had to, I could do likewise, but it would be nice to have
the tuner move with the rig when in recieve mode also, like the other
rigs do.
Thanks,
Duane
Thanks,
Duane
On Sat, 20 Jan 2007 19:47:58 -0500, "Carl Moreschi" <n4py@arrl.net>
said:
The first local osc outputs a frequency of 45 to 75 mhz (45 mhz higher
than
the operating frequency) in 2.5 khz steps depending on the operating
frequency. This frequency is controlled by the onboard firmware. After
the
first mixer, this produces an IF frequency of 45 mhz. Then local osc 2
runs
at a fixed 44.5425 mhz and converts the 45 mhz IF to a 455 khz IF.
Then
local osc 3 runs at a fixed 467 khz and converts the the 455 khz IF to
12
khz. This frequency then goes into the DSP section for detection and 1
hertz resolution. There is no way to monitor any of the oscillators
externally and determine the frequency closer then 2.5 khz because the
fine
adjustment to 1 hertz resolution is all done in DSP. Such is the nature
of
DSP radios. The old analog schemes of the past are gone.
Carl Moreschi N4PY
121 Little Bell Drive
Bell Mountain
Hays, NC 28635
----- Original Message -----
From: "dw" <bw_dw@fastmail.fm>
To: "Discussion of Ten-Tec Equipment" <tentec@contesting.com>
Sent: Saturday, January 20, 2007 5:46 PM
Subject: [TenTec] A question for those who know whats going on under
thehood
:)
Hey Gang,
Here is a Jupiter (under the hood) question.
The local oscillator 'A' , is it continuously outputting the frequency
which is displayed?
or is it outputting an IF frequency?
If answer is yes, it is outputting continuously, the displayed
frequency,
then next question is.....
Is there a way to tap onto a board and monitor the current frequency?
Thanks
Duane
N1BBR
--
dw
dw@sover.net
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--
dw
dw@sover.net
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